Sofa



FIG. 1 is a perspective view of an embodiment of a sofa showing my new design;

FIG. 2 is a top view thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a left side elevational view (right side elevational view is a mirror image thereof); and,

FIG. 5 is a rear elevational view thereof. 

CLAIM The ornamental design for a sofa, as shown and described. 